1. Field of the Invention
The present invention relates to a system and method for manufacturing disposable diapers with an elastic foam waistband.
2. Description of the Prior Art
There has been a large consumer demand for disposable diapers for many years. Typically, disposable diapers are fabricated with three layers: an outer, impervious barrier layer usually of a thin plastic; an inner, porous layer of a thin cellulose fiber; and an absorbent pad extending along a portion of the space between the inner and outer layers. Disposable diapers also have been manufactured with elastic banding along the portions of the periphery which encircle the baby's legs when the diaper is worn.
Recently, there have been investigations into the use of an elastic waistband along the portion of the periphery of the diaper which encircles the child's waist during use. In one arrangement, the elastic waistband is formed with a length of thin elastic foam which is stretched and then adhered between the inner and outer layers at the predetermined waistband locations. The manufacturing technique used to stretch the lengths of elastic waistband form employs plural pins which first penetrate the ends of each waistband foam length and then stretch the length across its longitudinal direction. However, the penetration of the waistband length with the stretching pins has several potential disadvantages. First, the penetration of the waistband length forms voids which sometimes tear during stretching Second, the stretching pins must necessarily be small, and if broken during the manufacturing operation may be hidden within the diaper until used. Third, the penetration process does not lend itself to the high speed manufacturing operations necessary for the efficient production of disposable diapers.